diff --git a/app/views/homework_attach/show.js.erb b/app/views/homework_attach/show.js.erb
index 3f8efb44c..fdae16fb5 100644
--- a/app/views/homework_attach/show.js.erb
+++ b/app/views/homework_attach/show.js.erb
@@ -4,6 +4,7 @@ $('#ajax-modal').css('height','569px');
 $('#ajax-modal').siblings().remove();
 $('#ajax-modal').before("<span style='float: right;cursor:pointer;padding-left: 513px;'>" +
     "<a href='#' onclick='hidden_homework_atert_form();'><img src='/images/bid/close.png' width='26px' height='26px' /></a></span>");
+$('#ajax-modal').parent().removeClass("alert_praise");
 $('#ajax-modal').parent().css("top","").css("left","");
 $('#ajax-modal').parent().addClass("alert_box");